The podcast episodes discuss upcoming books from several authors, including Adele Roberts' 'Personal Best', Dr. Robert Sapolsky's 'Determined: The Science of Life Without Free Will', and other unspecified upcoming books.

The topic of 'Upcoming Book' is related to the podcast episodes in that they provide information about and context around these upcoming book releases.

For example, the episode BONUS EP: Adele Roberts discusses Adele Roberts' upcoming book 'Personal Best', which details her journey of setting a Guinness World Record for the fastest woman to run a London marathon with a stoma bag. Similarly, the episode Dr. Robert Sapolsky: Science of Stress, Testosterone & Free Will mentions Sapolsky's upcoming book 'Determined: The Science of Life Without Free Will', which explores the implications of a deterministic view of behavior and the challenges of functioning without a sense of free will.